Aircraft engine and gun assembly



Nov. 12, 1935. M. 'BIRKIGT 2,020,872

AIRCRAFT ENGINE AND GUN ASSEMBLY Filed Nov. '26, 1934 y 1 dz Z 4 i lNVE-NTOR.

Marc. Dirk AT'fO RNEYS Patented Nov. 12, 1935 UNITED STATES PATENT OFFICE France December 2, 1933 12 Claims.

The present invention relates to systems including on the one hand an aircraft engine having its propeller shaft, which is driven through speed reducing gears, eccentrically positioned with respect to the crankshaft, and, on the other hand, a gun arranged to shoot through said propeller shaft.

The object of the present invention is to provide a system of this kind which is better adapted to meet the requirements of practice.

The essential feature of the present invention consists, while causing the barrel of the gun to extend through the propeller shaft, in fixing said barrel to the frame carrying this shaft and in providing, on the rear portion of the gun, means for maintaining the axis of.said gun in substantially fixed relation with respect to .the engine.

Another feature of the present invention consists in providing, besides this rigid fixation of the gun to the engine, a second fixation, or safety fixation, of another part of the gun to the engine, the latter fixation being made with a certain play so as to come into action only in case of the first fixation having broken.

These and other features of the present invention will result from the following detailed description of a specific embodiment thereof.

Preferred embodiments of the present invention will be hereinafter described, with reference to the accompanying drawing, given merely by way of example, and in which: I

Fig. 1 is a diagrammatic elevational view, part ly in section of a system according to the present invention;

Figs. 2 and 3 are sectional views showing de tails of the system of Fig. 1, on an enlarged scale;

Fig. 4 is a sectional view on the line 4-4 of Fig. 3.

In the system according to the present invention, the engine is made in any suitable manner. For instance it comprises two rows of cylinders inclined with respect to each other so as to form a V in'vertical cross section, both of these rows of cylinders being carried by a casing a.

This engine is provided with a speed reducing gear, for instance of the type including spur gearwheels, this gear serving to connect the crankshaft of the engine with a propeller shaft b, the axis of which extends, on the. rear between the cylinders of the engine. v

This propeller shaft is provided with an axial hole affording a passage'for the barrel of the gun to be fitted on the engine.

This gun is made in any suitable manner so that when its barrel is engaged in said hole of the propeller shaft it occupies the space left free by the various elements of, the engine.

According to the present invention, I provide means for fixing the barrel 0 of the gun to the frame d of the casing carrying the propeller 5 shaft, said means being. made in any suitable manner, for instance as shown in Figs. 1 and 2.

According to this embodiment, I provide, at the place where the barrel 0 of the gun is to penetrate in frame d, a ring e the bore of which is adapted to accommodate said barrel with the proper amount of play, said ring'being fixed in position, for instance by inserting it, when the parts are assembled, between the portion of frame (1 which is integral with the engine and the lid d of said. frame.

The barrel c of the gun is provided with a collar ,f adapted to bear against said ring, on the outer side thereof.

The end of the barrel is screw threaded and a nut g is screwed on said end, so as to tightly hold ring e between collar 1 and said nut, whereby the barrel of the gun is rigidly fixed to frame d.

Advantageously, this nut is given an elongated tubular shape so as to constitute a guide for the flames and a protection against them, at its front end The rear end 9 of said nut is adapted to bear upon the front face of ring e, preferably in the annular zone of this face that is close to the boreof said ring.

I further provide means for preventing the lubricant which serves to the lubrication of the bearings of the propeller shaft, and also of the speed reducing gear; from escaping from the casing at the place where the barrel of the gun 35. penetrates into said'casing.

These last mentioned means are advantageously of the kind of the devices commonly used for preventing leakage of lubricant at the place, where a revolving shaft projects from a casing. 40 Said means consist for instance of a kind of turhim one element of which turnsin the vicinity of the walls of another element which is staslight play is provided between the outer wall of i I part It and the inner wall of housing 1, but this play must be sufiicient for preventing contact in any.case. At least one of these cooperating cylindrical walls is provided with helical grooves as above explained. Of course, this flange it, instead of engaging in the propeller shaft, might as well engage around it.

In order to support the gun in proper position in the vicinity of the breech, the engine-is preferably provided, in its rear part, with a support f, integral or rigid with said engine. Such support cooperates with the rear part of the gun in such manner as to permit relative displacements thereof due for instance to dilatation resulting from heating of the gun.

It will of course be immediately understood that, as the front part of the gun is rigidly fixed to the engine, the rear part of said gun must be capable of sliding with respect to the engine.

An example of such a sliding connection is shown by Figs. 3 and 4.

In this embodiment, support 1 is given the shape of a slideway parallel to the axis of the gun. The gun is provided with a sliding element k adapted to cooperate with said slideway in such manner as to prevent any transverse relative displacement but to permit a sliding relative displacement in the direction of the axis of the gun.

The arrangement according to the present invention has the advantage that because of the fixation of the gun by its front part, recoil does not tend to produce a deviation of the axis of the gun as would be the case if the fixation was provided at the rear part of the gun. This advantage is the greater as the center of the fixation is nearer to the axis of the tube. Now, in the embodiment above described this center is located on the axis itself, so that recoil has no -g1m, these safety fixation means being so arranged as to be brought into play only in the event of the first fixation means being broken.

Advantageously, as shown in the drawing, these safety fixation means include a pin 1 extending both through slideway a and through sliding element is, said pin being carried without play by one of these elements (for instance the sliding element) and engages in elongated passages m carried by the other element.

Under normal conditions of working, pin 1 moves freely in said passages under theeifect of dilatation.

If, on the contrary, the front fixation means break, the safety fixation means prevent the gun from moving backwards beyond a certain distance, thus ensuring protection for the person located behind said gun.

While I have, in the above description, disclosed what I deem to be a practical and efficient embodiment of the present invention, it should be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the present invention as comprehended within the scope of the appended claims.

What I claim is: 1. A system including in combination, an aircraft engine, a frame for said engine, a propeller shaft journalled in said frame adapted to be driven by said engine, said shaft being provided with an axial hole, a gun the barrel of which is engaged in said hole, means for rigidly fixing the front end of said barrel to said frame, and means carried by said engine for movably supporting the real part of said gun. 5

2. A system according to claim 1 in which said front part of the barrel of the gun is provided with a collar,'said means'for fixing said front part of said barrel to said frame including, a ring fixed to said frame in such manner that said it) collar bears against one side of said ring, and a tubular nut screwed on the front end of the barrel of the gun and bearing against the other side of said ring.

3. A system according to claim 1 in which said 15 front part of the barrel of the gun is provided with a collar, said means for fixing said front part of said barrel to said frame including, a ring fixed to said frame in such manner that said collar bears against one side of said ring, and a tubular 20 nut screwed on the front end of the barrel and bearing against the other side of said ring, said tubular nut extending to a certain distance in the propeller shaft, toward the front so as to guide the flames issuing from the gun and pro- 25 test the propeller shaft against said flames.

4. A system according to claim 1 further including means for fixing another part of the gun to the engine in case of the first mentioned fixation means being broken.

5. A system according to claim 1 in which the means carried by said engine for movably supporting the rear part of the gun include a slideway carried by the engine, and a sliding element rigid with the gun fitting in' said slideway, so as to prevent transverse relative displacements of said slideway and said sliding element.

6. A system including in combination, an aircraft engine, a frame for said engine, a propeller shaft journalled in said frame adapted to be driv- 40 en by said engine, said shaft being provided with an axial hole, a gun the barrel of which is engaged in said hole, means for rigidly fixing the front end of said barrel in said frame, a slideway carried by said engine, a sliding element rigid with the rear part of the gun engaging in said slideway in such manner as to prevent transverse relative displacements of said slideway and said sliding element, one of the two last mentioned elements being provided with an elongated longi- 60 tudinal passage, and a pin fixed" transversely to the other element and engaging in said passage.

7. A system including in combination, an air-' craft engine, a frame for said engine, a propeller shaft journalled in said frame adapted to be driven by said engine, said shaft being provided with an axial hole, a gun the barrel of which is engaged in said hole, means for fixing the front end of said barrel to said frame in such a manner as to prevent axial displacement of said front end, and means carried by said engine for supporting the rear part'of said gun in such a manner as to prevent transverse displacements of the rear part of said gun while permitting axial displacements of said rear part.

8. In an aircraft, a gun with a barrel, means for rigidly fixing the front part of said barrel to the aircraft and means carried by said aircraft for movably supporting the rear part of said gun.

9. A gun according to claim 8, in which said front part of the barrel of the gun is provided with a collar, said means for fixing said front part of said barrel to the aircraft including a ring fixed to the aircraft in-such a manner that said collar bears against one side of said ring, 76

way carried by the aircraft, and a sliding element rigid with the gun fitting in said slideway,

so as to prevent transverse relative displacements of said slideway and said sliding element.

12. In an aircraft, a gun with a barrel, means foriixing the front part of saidbarrel to said aircraft in such a manner as to prevent axial displacement of said front part and means carried by said aircraft for supporting the rear part of said, gun in such a manner as to prevent transverse displacements of the rear part of said gun while permitting axial displacements of said 10 rear part.

MARC BIRKIGT. 

